IB/hfi1: Right size user_sdma sequence numbers and related variables

Hardware limits the maximum number of packets to u16 packets.

Match that size for all relevant sequence numbers in the user_sdma
engine.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/hfi1/sdma.h

@@ -849,7 +849,7 @@ int sdma_send_txreq(struct sdma_engine *sde,
 int sdma_send_txlist(struct sdma_engine *sde,
 		     struct iowait *wait,
 		     struct list_head *tx_list,
-		     u32 *count);
+		     u16 *count_out);
 
 int sdma_ahg_alloc(struct sdma_engine *sde);
 void sdma_ahg_free(struct sdma_engine *sde, int ahg_index);